1. Field of the Invention
The present invention relates to a liquid crystal display (LCD) device, and more particularly, to an active level shift (ALS) driver circuit capable of reducing the width of an external black matrix, a LCD device including the ALS driver circuit, and a method of driving the LCD device.
2. Description of the Related Art
A liquid crystal display (LCD) device is light weight, thin, and driven with low power consumption, and thus is widely used as a display device, such as a laptop or a portable television (TV).
The LCD device includes a gate driver and an active level shift (ALS) driver, and displays an image by adjusting light transmittance according to a signal applied to a plurality of control switches aligned in a matrix from the gate driver and the ALS driver.
The ALS driver uses two direct current (DC) voltages to generate an ALS voltage. The ALS driver maintains a previous ALS voltage while writing the LCD device by a gate-ON voltage and changes the ALS voltage by a gate-OFF voltage. Since the ALS driver includes a latch circuit to maintain the previous ALS voltage, a clock generator is required, thereby increasing the size of the ALS driver circuit.
As an external black matrix BM of the LCD device has been slimmed, the internal circuit of the ALS driver needs to be simplified.